There are no codes wrote on this, so it wasn’t clear at the time if there was a burden resistor already fitted. The Fronius Smart Meter WR is a bidirectional meter, which optimises self-consumption, records the load curve and controls the various energy flows.

Comprehensive Energy Monitoring: Our smart energy monitor is designed to help you monitor and manage your energy usage conveniently. I tried to describe the simple wire that forms something that looks like the letter U and hangs from the junction box. I don’t have much experience with CTs and I found no specific instructions as how to put the meter on the wire.Until I got the hang of this I was pressing it for too long (and a long press does someting else), so initially I was somewhat frustrated with it. While there might be cheaper options online, home automation can be complex, and having experts by your side can prevent costly mistakes.

For what it's worth, and for the guidance of others, these plugs fit the drain hole on a Perception Triumph 13. I started testing my new system and put 2 meters (one is the blue from OEM and one 30A model from the same manufacturer) on the same wire to see if they show any difference in measurements. I found that I needed to calibrate the bottom end of the sensor slightly too because it was picking up some interference and reporting about 60 amps when nothing was connected, so my lower end calibration value is actually 0. This product works very well with the Tuya Smart app, with accurate real-time display of power consumption.The best way to calibrate it is to attach the clamp around a cable with a known current running through it. But when I initially did the circuit I did omit the burden resistor and I wonder If I’ve damaged the ESP32. If your clamp is not tight around your cable - it will not measure accurately, equally if the cable does not pass through your clamp at 90degrees to the ferrite “core” - it may not be accurate. I’m sure I could have paid less for the CT clamp if I’d been willing to wait for a couple of months for it to arrive from China.